Results 241 to 250 of about 14,697,656 (278)

Dynamic birefringence of several high polymers

Journal of Polymer Science Part C: Polymer Symposia, 1964
AbstractThe complex strain‐optical coefficient, complex stress‐optical coefficient, complex modulus of elasticity and the corresponding loss tangent of phase angles between the stress, strain and birefringence have been measured for several high polymers in the frequency range from 0.001 to 10 cycles/sec.
R. Yamada, C. Hayashi, S. Onogi, M. Horio   +3 more
openaire   +1 more source

Liquid crystalline materials with high birefringence

Journal of Optical Technology, 2005
The mesogenic, optical, and dielectric properties of the new mixtures of high-birefringence nematic liquid crystals based on isothiocyanatotolanes are investigated, and examples of multicomponent mixtures with low viscosity and optical anisotropy Delta n approximately 0.4 are presented.
A. Spadlo, R. Dabrowski, J. Dziaduszek, E. Scibior, S. Urban, S. Gauza, S. T. Wu   +6 more
openaire   +2 more sources

Halogen Bond Unlocks Ultra‐High Birefringence

Angewandte Chemie International Edition
AbstractAnisotropy is crucial for birefringence (Δn) in optical materials, but optimizing it remains a formidable challenge (Δn >0.3). Supramolecular frameworks incorporating π‐conjugated components are promising for achieving enhanced birefringence because of their structural diversity and inherent anisotropy. Herein, we first synthesized (C6H6NO2)+
Jin Chen, Miao‐Bin Xu, Huai‐Yu Wu, Jun‐Yan Wu, Ke‐Zhao Du   +4 more
openaire   +2 more sources

High birefringence liquid crystalline materials

2008 IEEE/LEOS Winter Topical Meeting Series, 2008
In this paper, nematic liquid crystalline materials and its mesogenic and physicochemical properties (mainly birefringence, dielectric anisotropy, and viscosity) will be discussed. The influence of number and position of fluorosubstitution on the ability of nematic phase formation in broad temperature range and on the value and sign of dielectric ...
R. Dabrowski, S. Gauza, J. Dziaduszek, P. Kula, S. Urban, S. T. Wu   +5 more
openaire   +2 more sources

High Frequency Enhancement By a Birefringent Lens

Journal of Optics, 1980
A birefringent lens gives a focusssed image and a defocussed image of an object simultaneously in one plane. This property of birefringent lens may be fruitfully utilised for high frequency enhancement. The present paper suggests an experimental technique for achieving the same.
A. K. Chakraborty, B. Mandal Adhikari
openaire   +1 more source

Dynamic Birefringence of High Polymers II

Journal of Applied Physics, 1963
The time-dependence of birefringence was investigated in experiments involving relaxation at constant strain, extension at constant rate of strain, and periodically varying strain. The results of constant strain relaxation are calculated from the other two types of experiments using the linear phenomenological theory of birefringence relaxation. Strain-
R. S. Stein, S. Onogi, K. Sasaguri, D. A. Keedy   +3 more
openaire   +1 more source

Polarization Quality of High-Birefringence Single-Mode Fibers

AT&T Bell Laboratories Technical Journal, 1984
Coherent optical communications, integrated optics, and interferometric sensors require that single-mode fibers maintain a stable state of polarization. With a broadband source, wavelength averaging of the power in either orthogonally polarized HE 11 mode permits a simple measurement of the power transfer to the cross-polarized state (the h value ...
Frederick M. Sears, Jay R. Simpson
openaire   +2 more sources

High Frequency Polarization Modulation Method for Measuring Birefringence

Applied Optics, 1975
A high frequency modulation method utilizing a photoelastic polarization modulator for the measurement of optical birefringence is described and discussed. Although the apparatus has the high sensitivity required to measure very small retardations, the accurate measurement of larger retardations is emphasized and a particularly simple null detection ...
F A, Modine, R W, Major, E, Sonder
openaire   +2 more sources

The Theory of High Elasticity and Birefringence of Rubbers

International Journal of Polymeric Materials and Polymeric Biomaterials, 1980
Abstract On the basis of a “channel” model an attempt has been made to account for the limitation of the number of possible chain conformations in bulk elastomer. Each chain is supposed to fluctuate near its average position—the “channel”, determined by the conditions of bulk polymer formation.
openaire   +1 more source

Dodecagonal photonic quasi-crystal fiber with high birefringence

Journal of the Optical Society of America A, 2016
A photonic quasi-crystal fiber (PQF) with high birefringence is proposed. A dodecagonal Stampfli quasi-periodic lattice of air holes constitutes the cladding of the PQF. The PQF maintains the properties of high birefringence and single-mode operation regime in a wide wavelength range from 1.2 to 2.0 μm by optimizing the size of the air holes around the
Weicheng, Cai, Exian, Liu, Bo, Feng, Wei, Xiao, Hongfei, Liu, Ziming, Wang, Shuo, Wang, Taiyuan, Liang, Jianqiang, Liu, Jianjun, Liu   +9 more
openaire   +2 more sources